Regulatory Properties of Glutamine Synthetase from the Nitrogen-Fixing Phototrophic Bacterium Rhodopseudomonas palustris
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چکیده
Rhodopseudomonas palustris, Glutamine Synthetase Regulation, Adenylylation Glutamine synthetase from Rhodopseudomonas palustris is regulated via an adenylylation/ deadenylylation mechanism. The enzyme purified from ammonia-grown cells, released AMP upon treatment with phosphodiesterase, along with drastic changes in its pH and metal dependency. Kinetic parameters for enzyme-substrate interaction were also dependent on the adenylylation state of the enzyme, as was the influence of several nitrogenous feedback inhibitors on the catalytic activity. The adenylylation state of the enzyme was modified in vivo by the availability of ammonia.
منابع مشابه
Molecular Characterization of Glutamine Synthetase from the Nitrogen-Fixing Phototrophic Bacterium Rhodopseudomonas palustris1
Rhodopseudomonas palustris, Glutamine Synthetase, Dye-Ligand Chromatography, Nitrogen Fixation, Ammonium Assimilation The phototrophic bacterium Rhodopseudomonas palustris assimilated ammonium via glutamine synthetase and glutamate synthase. Diazotrophic and ammonium-grown cells had high levels of both enzymes, whereas enzymes of alternative assimilatory pathways were absent or had only low act...
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